Roof Rafter Length Table

A hip or valley rafter will be 18 long per foot of horizontal run on a 6 12 slope roof.

Roof rafter length table.

A common rafter will be 13 42 long per foot of horizontal run on a 6 12 slope roof. Includes result for hip valley factor slope factor and the roof slope in degrees. The tail or eave overhang must be added to the rafter length. If you add an eaves overhang dimension then the amount the rafter sticks passed the wall will be added to the rafter length.

The run of the rafter. Rise and run means that a 6 12 pitch roof has 6 of rise vertical for each foot of run horizontal. All we do now is use a calculator to multiply 1 610 by the measurement in the book. Rafter length calculator calculate the length of a rafter from the roof slope ratio of inches per foot and a building width measurement.

Rafter length using pitch v r 2 sqrt 1 p 2 where v overhang r roof span p pitch use our online rafter length calculator to quickly compute the length of the shed roof rafter by entering the measurements of overhead length of roof span pitch or angle. The difference in length of sequential jack rafters spaced 16 o c. 1 1543 x 1 610 1 858m. The length of the rafter.

This is the rafter length from the top cut to the seat plumb mark. Enter the value for the roof width outside to outside in feet inches and fraction inches and fraction or use the inches box to enter a value in decimals if that is your preference. Height of the scaffold. Roof rafter span use this table to determine the maximum lengths of roof rafters based on species and grade of lumber spacing dimensions load and slope.

For example in the rafter span table below the highlighted cell in the 40 live load table indicates that 2 x 8 southern yellow pine joists that have a grade of 2 that are spaced 24 apart can have a maximum span of 10 feet 3 inches 10 3 if designing for a live load of 40 lbs ft 2. Tail or eave length. This means that for every 1m the rafter travels horizontally the angled length of the roof will be 1 1543m. Using the 7 inch rise table and our 15 run the common rafter length is 17 43 8.

The rise of the rafter. The respective lengths for those two rafters and add them together. The length of rafter per meter of run is 1 1543.